a. Field of the Invention
The invention is based on a switched-mode power supply which contains a switching transistor as well as an isolating transformer having a primary winding and a secondary winding.
b. Description of the Prior Art
These require a relatively high level of component complexity, particularly if regulation information must be transmitted from the secondary side to the primary side in order to stabilize an operating voltage on the secondary side. Various embodiments are known for transmitting this information, for example using an optocoupler. DE 40 04 707 discloses a circuit in which a regulating signal is transmitted back via a transistor stage in a brief time interval during a quiescent phase of the isolating transformer.
The object of the present invention is to reduce the component complexity for switched-mode power supplies of the type.